Data Transformation Engine Type Designer Reference Guide

Chapter 9 - Partitioning Partitioning Types
You can tell the difference between the types by looking at the value of the
PaymentMethod Column. When the payment method is cash, the component
rule is $="CASH". When the payment method is a credit card, the component rule is
$="CREDCARD". When the payment method is a check, the component rule is
$="CHECK".
Note Notice how the component rules are used with identifiers in this type tree to define
payment types.